Most healthcare professionals (HCPs) have adjusted to the fact that a patient's first consultation will not be with them or their colleagues but with Google instead. Although it's certainly understandable why patients dealing with mysterious symptoms may find the search engine's allure irresistible, the resulting "diagnosis" often proves unfounded, if not downright terrifying.

Yet if HCPs now spend valuable time debunking misinformed self-diagnoses, will they regard it as progress if patients take things one step further by arriving at their initial visits with their own diagnostic test results?

With the growing market for home lab kits, which allow consumers to test for a variety of conditions with a simple mouth swab or finger-prick, it's a question that HCPs are soon likely to face.

Although the use of these kits to keep track of common biomarkers like cholesterol or blood sugar is unlikely to elicit concern, things become a bit more complicated when it comes to the growing number of tests designed to monitor thyroid function.

Some in the endocrinology community have expressed reservations regarding the reliability of these tests and their potential to contribute to misdiagnoses of hypothyroidism, while others see them as an inevitability that should be embraced for their ability to cut through red tape and identify patients who may otherwise be overlooked.

What Does Home Thyroid Testing Entail?

A cursory online search reveals multiple companies offering thyroid-specific home-testing kits, and as expected, their quality and reliability vary according to the manufacturer. However, established companies within this space, such as the US-based EverlyWell and UK-based Medichecks, appear to be operating with considerable caution in what they offer. The companies enlist licensed physicians and pathologists to analyze the blood samples in laboratories with the requisite certification.

Customers who are concerned that their symptoms may indicate thyroid dysfunction can choose from a variety of kits assessing relevant biomarkers, from basic thyroid-stimulating hormone (TSH) to a fuller assay consisting of free T3/T4 and antibodies to thyroid peroxidase and thyroglobulin. The kits are delivered directly to customers, who provide a finger-prick blood sample and return it in the mail.

The companies enlist licensed physicians and pathologists to analyze the blood samples in laboratories with the requisite certification (eg, College of American Pathologists, Clinical Laboratory Improvement Amendments). Shortly thereafter, customers receive in-depth reports identifying where their one-time sample exists on a continuum of biomarker ranges, alongside additional context and educational materials.

"Because they have not had a consultation with the customer, they do not diagnose conditions," says Sam Rodgers, MBBS, MRCGP, medical director at Medichecks. "They do advise when results increase the likelihood of a customer having a condition and will direct them back to their own doctor when this is appropriate."

Although there was concern that HCPs would balk at having diagnostic testing occur before they've ordered it, that hasn't been borne out by anecdotal experience, explains Marra Francis, MD, executive medical director at EverlyWell.

"Initially, there may be some concern if they have no idea who the physician is listed on the lab result, but when we explain to them that we’re working with the Physician Wellness Network and that everything is certified, they don’t seem as upset," she says. "We very rarely hear that physicians have just completely discredited the results and didn't act upon them in one way or another."

At-Home Advantages

Rather than being an extension of the Internet-driven trend toward patients self-diagnosing, home testing actually serves as an informed corrective, says Francis.

"Let's face it: Every consumer is a Google MD at this point," Francis says. "I look at us as a bridge between a consumer having obscure or random symptoms at home and then actually getting into the doctor's office for a constructive, direct consultation."

Perhaps surprising for an out-of-pocket expense, the companies say that many patients gravitate toward these tests for economic reasons. In the United States, such tests can often be covered by flexible spending and health savings accounts. Where patients are likely to find continual bills in their mailbox for straightforward lab work, this has an obvious appeal.

Costs are kept relatively low, ranging from approximately $40 to $150, depending on the biomarkers assessed. Although this cost is not negligible, it does come with the benefit of being a transparent, one-time fee.

In an environment where even insured patients are likely to find continual bills in their mailbox for straightforward lab work, this has an obvious appeal. It also benefits patients who have high deductibles or whose insurance refuses to pay for a wider battery of testing.

Medichecks' Rodgers says that there are also economic advantages to the United Kingdom's National Health Service (NHS), although perhaps not as obvious as the US payer models.

"One of the benefits of self-testing is that people can attend their first doctor's appointment with their test results rather than having to arrange blood tests and then attend a second appointment. This has benefits both for the NHS in terms of saving appointments and for the patient who only has to take one day off work instead of two."

Endocrinologists' Concerns

Home-testing companies commonly advertise their ability to reach patients who might otherwise be reluctant to attend in-office visits, whether because of geographic isolation or physical limitations. Yet it is also probably true that thyroid tests are being purchased by those whose concern has been stoked by increasing coverage in the press of hypothyroidism as a catch-all diagnosis for a variety of often vague symptoms.

"I challenge you to find someone who doesn't have at least one hypothyroid symptom, whether it's feeling anxious or tired, or gaining a few pounds or being constipated," says Stephanie L. Lee, MD, PhD, an associate professor of medicine at the Boston University School of Medicine and director of the Thyroid Health Center and the Thyroid Nodule and Cancer Research Center at Boston Medical Center.

"These are very common symptoms, especially in the middle-aged female population who get thyroid disease. And if you look at the lay literature, it's been long-standing to see these symptoms linked to hypothyroidism as a possibility. It's something you see in women's magazines all the time."

This is not to say that these manufacturers are creating a market from thin air. The American Thyroid Association (ATA) estimates that of the 20 million people in the United States with some form of thyroid disease, 60% are unaware of their condition, which if left untreated can cause significant risk for morbidity like cardiovascular disease and osteoporosis.[1]

However, there is a growing concern that the common practice of treating subclinical hypothyroidism with levothyroxine does not lead to improvements in quality of life or related symptoms, as reported in a recent JAMA meta-analysis.[2]

"At first consideration, it would seem that most of the individuals using these kits at home would be likely to have mild or borderline disease. So there is definitely the concern that these kits might be the starting point for treatment that may not have a benefit," says Jacqueline Jonklaas, MD, PhD, assistant professor in the division of endocrinology and medicine at the Georgetown University Medical Center in Washington, DC, as well as secretary-elect and an officer of the board of directors for the ATA. "Also, any treatment that is not needed is not innocuous. There are considerable risks of overtreatment if treatment is not monitored."

Given that TSH levels are known to fluctuate, it is crucial that any treatment decisions be delayed until patients undergo repeat testing to confirm the findings of the home kits, says Jonklaas.

"Another potential concern about home testing is that patients may be trying to understand results without the appropriate context or support," she says. "So it is critical that any abnormal results trigger a physician's visit, confirmatory testing, and further discussion with a physician."

Embracing the Change

Because established home-testing companies are offering information rather than diagnoses or treatment, there is little risk of curious consumers being harmed by what they find, according to Terry F. Davies, MD, co-director of the Thyroid Center at Mount Sinai Union Square in New York City.

"I'm in favor of home testing and don't have a problem with it as long as these customers find themselves getting to an MD eventually," says Davies. "I think this is more for the educated consumer who wants to check up. They've read that thyroid failure causes weight gain and depression, and they want to make sure their thyroid is okay. Why go to the doctor just for a simple blood test? All that matters is that the test be valid."

There also appears to be a general acceptance for using these tests in patients with established thyroid conditions, for whom continued monitoring can present logistical challenges, ranging from finding the time to visit a lab to incidental fees incurred when they do, such as paying for parking and tolls.

As an example of a patient who might benefit from home testing, Lee mentions those with thyroid cancer who are often required to be in a hypothyroid state before they receive radioactive iodine treatment.

"Often I will just make the patient go without the medication for 5 weeks, and if they're not hyperthyroid after that point, they won't be," says Lee. "But that means they have probably endured an extra week or two of being low. Home monitoring might be very useful in that situation."

When Cultivating Trust, Evidence Still Reigns

When one talks about disruptive diagnostic medical technology, the cautionary tale of the blood testing company Theranos is never far from mind. Perhaps medicine's most high-profile "Emperor's New Clothes" parable of recent years, the company's fraudulent activities were a blemish on the industry.

It's an unfair comparison, as home thyroid testing companies aren't selling anything new but simply connecting customers to established technology. However, it has had an upside, according to Walter McAndrew, director of lab operations at EverlyWell.

"That skepticism is healthy for the industry as a whole," he says. "We firmly believe that if you're not doing anything wrong, you [shouldn't] have anything to hide. That's the mantra we follow on a number of different fronts."

To that end, the company is moving more aggressively to publish its results, cultivating a greater presence at major medical meetings and increasing its involvement with relevant physician societies.

It's a path that Mount Sinai's Davies thinks will prove enticing for any endocrinologists who may find themselves still on the fence about these tests.

"We would want to know whether the test has been subjected to careful clinical studies, which includes published reports that are then peer-reviewed. That would be something the professional societies can help the manufacturer organize and perform, and would be a great sales pitch."

Medichecks is also investing more heavily in the evidence space by commissioning research into the effects of self-testing on health anxiety levels.

"There has been surprisingly little research performed in this area, and none that we are aware of that is directly relevant to how we operate," says Rodgers.

It will be interesting to see what this research uncovers. Although patients have clearly grown more comfortable taking elements of their care into their own hands, there remains a large gulf between receiving a diagnostic report and having someone you trust tell you what it means. Google may remain the concerned patient's first stop, but there is still no replacement for the human element in contemporary healthcare.